Air Transfer Grilles from Pyroplex are suitable for use in fire doors for up to 60 minutes fire resistance. In normal use, they allow air to circulate and move throughout a building. In the event of a fire, however, the fire vents close to provide a fire barrier.
They are available in 5 different sizes, each with matching face plates in 2 different colours to suit your door.
Air Transfer Grilles may also be referred to as fire vents, intumescent grilles, intumescent vents, or fire blocks.